Golf-swing practice devices have been provided in two basic forms. One form that involves a golf practice mat is represented by U.S. Pat. No. 3,311,377 comprising a cushioning mat adhered to a hard board with a transparent sheet of polyester that overlies the mat and that has on the underside thereof white markings representing golf ball positions and reference lines indicating the correct direction of swing for various strokes, namely a straight in-line stroke or a fade (slice) or draw (hook) stroke to a target. With a marker affixed to the sole of the club head, the golfer takes practice swings over a golf ball image that is below the surface of the polyester sheet. The mark left on the sheet after each swing by that marker will indicate to the golfer the accuracy of the swing, thus allowing the golfer to make adjustments in stance, grip and/or body pivot necessary to achieve the desired direction of the golf club head over the image of the ball, which may be in-line or either from the inside to the outside (draw or hook) or from the outside to the inside (fade or slice) relative to a direct line to a target. A suction cup tee may be placed over the image of a ball to allow for actual practice strokes.
For either practice swings or actual strokes, the device of the aforesaid patent would be cumbersome to carry for use on a driving range or golf course. It would thus be best suited for use in one's own backyard for practice swings, but then one would not have an opportunity to test the swing with an actual stroke immediately after seemingly perfecting the swing to see if it will in fact produce the desired in-line, draw or fade stroke.
Another form of a golf-swing practice device that may be readily used on a driving range or a golf course is represented by U.S. Pat. No. 3,899,179 comprising a disk with an aperture for a golf tee. The disk is marked with a line passing through the center of the aperture to be aligned with the direction of the target. A string is attached to the disk at a point 90.degree. from an arrow indicating the direction of the target. When in use, the string is placed on the ground in a line perpendicular to the line indicating the direction of the target to serve as a guide for positioning the golfer's stance. Such a golf-swing practice device is thus quite limited in providing a guide for improving consistency in the golfer's in-line stroke. What is required is a golf-swing practice device that may be readily carried in a golf bag to a driving range or golf course for use not only as a guide to position ones stance relative to a golf ball for an in-line stroke but also as a guide for a draw or fade stroke.